Amanda, what Grid version do you use currently?

We don't recall any memory leaks issues thus far, since they have been progressively addressed from time to time. Make sure you run latest builds of WebUI Framework and WebGrid assembly.

Sorry, I am running version 6.0.7200.213

Hm, version 6.0 should be fine. In addition to Update Panel, do you also use other components in your page? The Grid is unlikely to cause the issue as we also used it very extensively in our application.

Have you tried in other browsers and compare the results? I.e, Firefox 3.5, Safari 4, etc.

Only standard asp.net textboxes.  I keep going back to the viewstate getting large, but not sure why it only occurs after longer use.  Would the webgrid create a large amounts of view state?

Amanda, WebGrid produces very minimal viewstate which usually consist only the setting required to be persisted. If your Grid is created in design time (i.e, all settings are declared in aspx), you can even set ViewStateStorage to None. That way, WebGrid will not produce any view state at all and still fully functional.